AirPOS does not automatically generate barcodes for your products. Many of our users prefer to generate their own barcodes which they then print off using a barcode/label printer.
Almost any sequence of numbers and/or letters can be converted into a barcode as a barcode is simply a visual representation of that sequence by varying the widths and spacings of parallel lines.
There are a number of free barcode generator sites available such as the following where you can enter a sequence of numbers and a barcode will be generated.
https://www.barcodesinc.com/generator/index.php
http://barcode.tec-it.com/en
Once you have generated your barcodes you'll need to print them off as labels.
We recommend the Dymo Label Writer 450, which is a simple and reliable label writer
How to use the Dymo LabelWriter to Print Barcoded Labels for your Products